Background This article is a case study about a surveillance system deployed in a Latin American city that collects and analyses geocoded historical crime data in order to identify crime hot spots. Analysis The case study focuses on the adoption of this technology by data collectors and the institutional cultures that mediate its workings. The article documents the conflicting adjustment strategies carried out by low-level police officers when the same crime data that they help to produce are operationalized as labour performance indicators. Conclusion and implications Drawing from scholarship in the field of critical data studies, this work situates the practices of data generation within institutional power relations to shed light on the particular politics at play in data-driven policing systems in the Latin American context.